ADI rolls new demods and PLL

Today, Analog Devices Inc. (ADI) has released two new quadrature demodulators and a new phase locked loop (PLL) for use in wireless infrastructure and point to point systems. Last week, I spoke to Ashraf Elghamrawi, ADI's Product Marketing Manager about these new RF ICs.

Long known for their PLLs and RF detectors, ADI has been expanded its portfolio and now is offering two new demodulators that offer high integration. Here are the specifics:

The ADRF6806 integrates an I/Q demodulator, PLL, VCO, and multiple LDO regulators. Elghamrawi points out that the integrated product maintains the same electrical performance as the dsicreate solution, with all performance specifications staying the same. The RFIC is manufactured using a SiGe BiCMOS process. It also features an SPI port, which allows desingers to program features in the chip. For example, it can accept an external LO instead or a low power mode. The LO frequency range is 50 to 525MHz.

"We've used a high performance mixer core, which gives us very high dynamic range and a low-noise VCO. Combined, this gives us a great EVM performance (overall receiver chain performance) of better than -45 dB over a broad RF input range of +35 dB. It can accept input signals over a 35dB range and still keep the overall performance at -45dB. This is very important because it allows receiver designers to maintain the signal power," observes Elghamrawi.

The ADRF6807 is essentially a higher frequency version of the ADRF6806, with an LO frequency range of 700 to 1050MHz. The EVM for this part is -38dB.

The ADF41020 is an18 GHz PLL frequency synthesizer. It consists of a low noise, digital phase frequency detector (PFD), a precision charge pump, a programmable reference divider and high frequency programmable feedback dividers (A, B & P). Elghamrawi reports that it is the highest frequency PLL on the market. Typical applications include microwave point to point, VSAT radios, and test equipment. It can also be used for lower-frequency regular wireless infrastructure. The beauty of this part is that it eliminates the need for a fequency doubler, which will reduce BOM, size, and cost. It is also software compatible with ADI's 6, 7, 8 GHz PLL. So, if a designer wanted to upgrade and eliminate the frequency doubler, it would be a simple board spin.

Price & AvailabilityADRF6806 and ADRF6807 are priced $9.98 each in 1,000 quantities. Sampling and full production quantities are available now. The demodulators are housed in a 40-lead 6-mm 6-mm LFCSP. ADF41020 is priced at $12.77 each in 1,000 quantities and is sampling now. It is housed in a 20-lead LFCSP.